package com.tarzan.reptile.pdf;


import javassist.*;

import java.io.*;
import java.util.ArrayList;
import java.util.Enumeration;
import java.util.List;
import java.util.jar.JarEntry;
import java.util.jar.JarFile;
import java.util.jar.JarOutputStream;

/**
 * @date 2022-05-16
 * @user tarzan
 */
public class PDFJarCrack {


    public static void main(String[] args) throws Exception {
        String jarPath = "E:\\maven_repository\\com\\aspose\\aspose-pdf\\21.8\\aspose-pdf-21.8.jar";
        crack(jarPath);
    }


    private static void crack(String jarName) {
        try {
            ClassPool.getDefault().insertClassPath(jarName);
            CtClass ctClass = ClassPool.getDefault().getCtClass("com.aspose.pdf.ADocument");
            CtMethod[] declaredMethods = ctClass.getDeclaredMethods();
            int num = 0;
            for (int i = 0; i < declaredMethods.length; i++) {
                if (num == 2) {
                    break;
                }
                CtMethod method = declaredMethods[i];
                CtClass[] ps = method.getParameterTypes();
                if (ps.length == 2
                        && method.getName().equals("lI")
                        && ps[0].getName().equals("com.aspose.pdf.ADocument")
                        && ps[1].getName().equals("int")) {
                    // 最多只能转换4页 处理
                    System.out.println(method.getReturnType());
                    System.out.println(ps[1].getName());
                    method.setBody("{return false;}");
                    num = 1;
                }
                if (ps.length == 0 && method.getName().equals("lt")) {
                    // 水印处理
                    method.setBody("{return true;}");
                    num = 2;
                }
            }
            File file=new File(jarName);
            ctClass.writeFile(file.getParent());
            disposeJar(jarName, file.getParent()+"/com/aspose/pdf/ADocument.class");
            } catch(NotFoundException e){
                e.printStackTrace();
            } catch(CannotCompileException e){
                e.printStackTrace();
            } catch (IOException e) {
            e.printStackTrace();
            }

    }

    private static void disposeJar(String jarName, String replaceFile) {
        List<String> deletes = new ArrayList<>();
        deletes.add("META-INF/37E3C32D.SF");
        deletes.add("META-INF/37E3C32D.RSA");
        File oriFile = new File(jarName);
       if (!oriFile.exists()) {
            System.out.println("######Not Find File:" + jarName);
            return;
        }
        //将文件名命名成备份文件
        String bakJarName = jarName.substring(0, jarName.length() - 3) + "cracked.jar";
        try {
        //创建文件（根据备份文件并删除部分）
        JarFile jarFile = new JarFile(jarName);
        JarOutputStream jos = new JarOutputStream(new FileOutputStream(bakJarName));
        Enumeration entries = jarFile.entries();
        while (entries.hasMoreElements()) {
            JarEntry entry = (JarEntry) entries.nextElement();
            if (!deletes.contains(entry.getName())) {
                if(entry.getName().equals("com/aspose/pdf/ADocument.class")){
                    System.out.println("Replace:-------" +entry.getName());
                    JarEntry jarEntry = new JarEntry(entry.getName());
                    jos.putNextEntry(jarEntry);
                    FileInputStream  fin = new FileInputStream(replaceFile);
                    byte[] bytes = readStream(fin);
                    jos.write(bytes, 0, bytes.length);
                }else {
                    jos.putNextEntry(entry);
                    byte[] bytes = readStream(jarFile.getInputStream(entry));
                    jos.write(bytes, 0, bytes.length);
                }
            } else {
                System.out.println("Delete:-------" + entry.getName());
            }
         }
            jos.flush();
            jos.close();
            jarFile.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    private static byte[] readStream(InputStream inStream) throws Exception {
        ByteArrayOutputStream outSteam = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = -1;
        while ((len = inStream.read(buffer)) != -1) {
            outSteam.write(buffer, 0, len);
        }
        outSteam.close();
        inStream.close();
        return outSteam.toByteArray();
    }
}